Electrical heating device



May 26, 1925. A 1,539,497

A. LONGORIA Y ELECTRICAL HEATING DEVICE Filed March 27. 1922 INVENTOR. ong/arid ATTORNEYS Patented Mey 26, 1925..

UNITED STATES* Nimmo -i ATENT NoFiici-'L VLOII'GOB`.I,A, OFCLEVELAND, 01110, ASSIGNOR T THE'W. B. MCALLISTER COMPANY, F CLEVELAND, 0R10, A. CORPORATION OF OHIO.

ELECTRICAL murinek DEV-ron -appiimion nica laren 27,1922. serial No". 547,022.l

To all -w'lwm it may co noem.' Be it known that I, ANTONIO LoNcokIA, y a citizen of the United States, and a resident of Cleveland, county of Cuyahoga, and State I of Ohio, have invented'a new and useful Improvement in Electrical Heating Devices,

` of which the following is a' specification, the

- principle of theinvention being herein ex- .Aplained and'- the bestmodein which I have A l0. contemplated applying that principle, so as to distinguish it from other inventions. The .present'ixnprovements relating as inn f dicated to velectrical heating devices, vare f more particularly directed to a new and iin- .15 proved electrical stove. Oneo' the principal objects' of the invention vis the provision of a simple and inexpensive device of this type o which ma be constructed with a few simple -parts an may then be readily 'assembled into the nished device. Further objects of the invention are improved 'means' for' mounting the heating element -and for protecting and coiling the frame-work' of thedevice. 4To the accomplishmentV of the foreu going and related ends, said invention, then,

.consists of the meanshereinafter fully .de-

scribed and particularly pointed out.v in the claimsf The annexed drawing and the following description' set forth in etail certain mecha- 'nism embodying the invention, 4sjuch disclosed means -constitutin however,` but oneof various mechanical' ormsl in;which the principle ofthe invention may bez'used.

In said annexed' drawing y 1V is a vplan view2 offmy improved stove, part of the same being show'nin section; Fig. 2 is a vertical section on' the line 242, Fig. 1; Figs. 3 and 4 are other vertical ines 3-3 and .respectively, in Fig. 1; Fi 5 is a sectional view sections on the through a portion o Vone of the connecting wiresi-and Fig. Gfis a section showinga modified type of locking means between the frame members.

. My improved stove consistsl of a rame.4 workformed in two arts, 1 and 2,the partj 1 being provided `wit an open .central por-.

a series of transverse ribs 3,

.Y and longitudinal ribs 4 which form an open' tion crossed4 by 'd-iron for supportin the articles or, re- ,itacles to beheated. frame` member .l 1 is `provided with legs5. the corners,

` upper frame member 1, an

`electrical insu-lation. The heating coil which are integral with this frame member,` this. entire part' being conveniently formed vout of a single stamping.

8 .which are formed integrallywith. the o y vare turned in Wardl'y to engage against and beneath a.

lowei-fframe member 2 when. the. latter hasbeen'ass'embled within the upper member.

The heating element consi-sts lof aresilient coill() which is mounted upon a sheetof in sula'tingiand refractory material-formed Ito fit snugly within the upper frame member 1, and to engage against an inwardly extending-flange 12 therein.y This flange is so forme'dand thecoil 10l is so mounted onthe .plate 11, that the coils are brought a suitable distance belowfthe openings between theribs 'Band 4 in -the'upperv frame member to give the best heating elect on any receptacle placed upon the stove without impairing the to a contact or' terminal inthe form' of a 8.0 I 10 is connectedat one end 1 screw l13 and Washer 14, the coil being held ybetween the washerand.the sheet 11 of reractorymateriaL The other end vof the coil is similarly fastened beneath a secondscrew '13 -and washer 14', and the coil is then carried backend-forth across a plate, 11 and secured at the point-s where it is bent along the.

sides of this plate in hooks 15, which are.

providedy with downwardly extending angle portions 16', whchvfit into slots 17 in. the sheet `11. ,These hooks are adapted to be engaged inthe sheets vby having the lower portion '18' passed through the slot after-- which the hook is turned'to bring it into position shown in Fig. 4, and the co1l'10'is `then engaged over and inthe hook ortion '15. .When so engaged, the coil is s ightly stretched and the tension in this` coil is sui- .v ycientto maintain.l the hook from any aecidental engagement Vfrom theslot 17 while permitting convenient removal'of' the hook.

and' coil. when necessary for repairs or` replacement. v U' From the two screws 13 and 1 3', wires are led through refractory and insulating bushings 19 and 20 which are provided with transverse slots adapted to slip over the edges of Ithe plate 2 in lateral recesses or slots 22 which are formed at either end of this plate, Only one of these two slots is used for these insulating bushings 19 and 2() but the slots are formed in either end to .free of its insulating covering at the point where it is held by the terminal post 13 up I to and through its passage through the refraetory insulated bush-ing 20. An eX- tremely high heating is maintained in the resistance coil 10 and this heat of course passes along the connections 23 and is high enough to melt certain of the ingredients in the insulated covering on the connecting wire up to the point where these connecting wires to pass outside of the space between the lower plate 2 and the refractory plate 11. It is for this reason that the insulating covering is removed and asbestos or other refractory yarn is wound about the bare wire and then cemented into place by a suitable refractory cement, such for eX- ample, as sodium silicate. This coating will not melt or burn under the high temperature ofthis portion of the wire and also serves to fix the wires in the bushings 20 and prevent their being pulled through the bushlngs, and in this way, pulled through the terminals. The bushings themselves are formed of lava. and are capable of withstanding very much higher temperatures than that maintained in the space between 2 and 11.

It will be noted that the corners 24 of the lower plate 2 are eut out and this provides a passage-way upward along the inner sides of the four legs 5 and to the lower portion of the refractory plate 11. Air is allowed to pass up through these corner openings into the space between the lower plate 2 and the asbestos plate 11, and is then carried through the plate 11 by means of a series of openings 25` along the two sides of this plate. After passing through the holes 25 this air is heated by the coil 10, and then passes upwardly through the grid-iron and mto Contact with the receptacle or article which is placed thereon. By causing the air which is heated, to be drawn upwardly along and against the inner sides of the fom legs .of the frame, these legs are cooled very considerably and in this way the outer frame-work of the stove is cooled to facilitat-e handling and to prevent overheating of the metal.

In Fig. 6 I have shown a modified means for attaching together the upper frame member 1 and the lower plate 2. In this form the upper member 1 is provided with the same depending flanges as in the previous form `but these lianges are now provided with slots 30 while lugs 31 are stamped ont from the upwardly extending flanges 6 on the plate 2, these lugs 31 then being bent to pass through the slots 30 and up along the upper sides of the flanges 7.

The simplicity and convenience of assembling my improved stove will be apparent from the foregoing description. The frame-work may be formed from two stampings while the heating unit may be assembled outside of the stove on the refractory plate 11. In assembling the device, the said platell and the heating element thereon, are pressed into the upper portion 1 of the frame until it rests against the flange 12. The plate 11 is formed of a size adapting it to fit snugly within the sides of the frame 1. The heating velementv is then secured in this position by pressing into place the bottom of plate 2, the flanges 6 of which engage against the lower side of plate 11. The parts are then secured in this relation by bending over the lugs 8. The device may be equally readily taken apart by merely bending back the lugs 8 and withdrawing first the plate l and then the plate 11 with its heating coils.. Before inserting the plate 1, the insulating but-tons 19 and 20 are slipped into one of the recesses 22 inthe ends of this plate which fixes the wires with respect to the stove and prevents the accidental pulling out of the wires from beneath the terminals 13 and 13.

Other modes of applying the principle of my invention may be employed instead of the yone explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or thie equivalent .of such stated means .be employed.

I therefore particularly point ont and distinctly claim as my invention 1. In a devicevof the characterdescribed. the combination of a frame member provided with ay perforated supporting surface. a depending flange along the sides of said surface and a, plurality of legs` depending from such fiange, va bottom plate engaging within and between such flanges on said frame member, and a heating element mounted between said frame member and said plate, said bottom plate being provided with openings adjacent each of said legs on said frame member, whereby air may pass upwardly valong `said legs to said heating element.

lll() 2.2In a device of thecharac-ter described,

the combination of a frame niember provided with a perforated supporting surface, a depending flange alongthe sides of said Qurface and a plurality-of legs depending from such flange, a refractory insulating plate bearing an Ielectrical heating elcnient on its upper surface, said plate being mounted between such flanges on said'fraine member, and said plate being provided 'with a plurality of openings therethrough, a` bottom plate provi-ded with flanges fitting v within such flanges on said framemembei,

such bottom plate flan es engaging said re- `fra-ctory plate, and sai bottomplate having .openings therethrough adjacent said legs` on saidframe member.y

An electrical heating device comprising a plate provided with spaced slots there# in and two terminalfposts, an electrical resistance coil. having its ends connectedto said terminal postshooks 'mounted in such slots in said plate, and saidcoilbeing secured at different points along its length to' said hooks, said hooks beingispaced to reuire tensioning of said coil-.when attached,

tiereto. p

4. An electrical heating device comprising .a (plate provided with spacedslots therein an two terminal posts, an electrical resistance coil having its ends connected to .said terminal .mountedin such slots in said plate, and

posts, hooks removably said coil being removably secured at different points along its length to. said hooks, said hooks being spaced to require tensioning of said coil when attached thereto, and said hooks being formed'to disengagefrom `such slbts when twisted in a direction' opposite to the tensioning action of said coil,

whereby said hooks are held against accidentalremoval while said coil ,is attached thereto.

5. In a. device of thecharacter described,

the combination of metal frame memberskfitting one within the other to provide a. -space therebetween, aheating coil mounted' between said members, one of said members being provided with a slot 1n one-side, re-

, 'the combination of spaced frame members,

an. electrical heating coil mounted therebetween', one of said members being provided 5 with yanopening therein, Ia refractory bushside walls.

lng mounted in such opening, a wire leading from said .heating coil through said bushing, and a 'refractory coating encasiiig said wire Aand extending from its point'of 'attachment to said' coil to a point beyond said bushing. t' I 8. In a, device of the character described,

-the combination of spaccdfranie members,

an electrical heating coil mounted therebe- "twee'n, one of s aid members being provided with an opening therein, a refractory bushing mounted in such opening, a wire leading from said heating 'coil through said busliing, and arefractory coating encasing said wire and extending from its point of attachment to said coil to a point beyond said bushing, said coating filling the interior of said bushing and fixing said wire against movement therethrough.

9. An electric table vstove comprising a.

one-pecebody, a pan having its marginal edges .supported by said body, an insulator having its marginal edges supported by the mar inal edges of said pan, and a sinuous heating element on said insulatonf 10. A n electric table stove vcomprising a one-piece. body, said one-piece body having a.A foraminous cooking top with the heating.

element'spaced from and below said cook- "-5 ing top, a pan having its marginal edges supported by said body,.an insulator having its marginal edgesv supported by the marginal edges of said pan, and a sinuous heating element on said insulator.

1l. An electric table stove comprising a one-'piece body, a .pan having its marginal 'edges supported by said body, an insulator having its marginal edges supported by the marginal edges of said pan, a sinuous heat'- ing element on'sa-id insulator, and said body having side walls and legs with said pan 'supported by inturned lower edges of the side walls. l I An electric table stove comprising a4 one-piece body, a pan having its marginal edges supported by said body, an insulator having its marginal edges supported bythe marginal edges of said lpan, and a sinuous heating element on'said insulator, 'said insulator having binding posts and coil holders for said sinuous heating element, and said pan having an. insulator for leading 'out wires..

-13.'Asla new article of manufacture, an electric stove body pressed from sheet metal to form a foraminous cooking top and legs.

' 14.' As a new article of manufacture, an.

electric stove body pressed from sheet metal to form a foraminous cooking top having side' walls with legs 15.*.As a new article of manufacture, an electric stove body pressed from sheet metal -at the juncture of the l to form.' a foraminous cookingtop having' side walls with legsL at the juncture of the Vside Walls, and said side Walls having inturned lower edge portions adapted for supporting a heating element in said body.

16. In an electric table stove, a flat insulator, a bared sinuous heating element on said insulator extending' from end to end of said insulator, and means at the ends of said insulator holding the ends and intermediate portions of said heating element.

17. In an electric table stove, a at insulator, a bare sinuous heating element on said insulator extending from end to end of said insulator, means at the ends of said insulator holding the ends and intermediate 15 portions of said heating element, and a pan under said insulator supporting the ends and sides of said insulator with said insulator in spaced relation to said pan.

18. An electric table stove comprising a foraminous cooking top, a. bared sinuous heating element below and in spaced relation to said cooking top, an insulator under said heating element and supporting said Iheating element, and a pan under saidV insulator in spaced relation thereto, said pan supporting said insulator.

Signed by me, this 24th day of March,

ANTONIO LONGORIA. 

